1. Field of the Invention
The invention relates to emission containment and alignment apparatus and method for fluid systems, including pumps and valves.
2. Description of the Prior Art
Fluid systems and their components, such as pumps and valves, comprise mechanically moving parts. In order for such parts to move with respect to each other, there must be some degree of clearance between them. This clearance provides a flowpath for fluid to escape.
Prior devices have used compression packing as a primary seal for the system. Such systems may incorporate packing followers to apply pressure to the seal. Such systems are durable and are particularly suited for use in abrasive services. However, there may be a number of disadvantages in using compression packing in certain applications, such as where volatile organic compounds (hereinafter "VOC's") are involved. Use of compression packing, alone, has not proved effective in eliminating or reducing to desired amounts the level of VOC emissions. Conventional packing follower systems typically allow product leakage to the atmosphere along both the inside diameter and outside diameter of the compression packing, and do not provide for shaft misalignment during installation. Typical use of compression packing may also lead to excessive wear of all contacting parts causing a reduction in the packing estimated sealing life as well as decreasing the overall efficiency of the system. Further, compression packing typically requires the use of lubrication to maintain the effectiveness of the seal. Prior systems may leak down the shaft, through a pump stuffing box outside diameter, through any split of the packing follower, or through other means. Conventional packing follows systems typically involve manually installing individual units of compression packing within a stuffing box. Such installation may be subject to installation error and it may be difficult to effectively place the compression stuffing within the stuffing box.
It may be desirable that emission containment systems be aligned very near the center line of the pump shaft. Prior systems require the installer to visually align the emission containment gland, which may cause misalignment of the system with respect to the shaft, thereby causing damage to either or both of the shaft or the emission containment system, causing the system to lose efficiency, and reducing the expected life of the system. Prior sealing members may incorporate seals that require constant contact and pressure on the shaft, thus causing undue wear on the shaft and the seal thereby creating a gap whereby VOC's may not be contained.
Prior systems may have involved high maintenance costs, short life spans, and/or have been less than effective in reducing or eliminating VOC release into the atmosphere or inflow of fluid into the system. Accordingly, prior to the development of the present invention, there has been no apparatus and method for emission containment for use in fluid systems that provides efficient and effective sealing and alignment means used in connection with an emission containment system. Therefore, the art has sought an apparatus and method for emission containment for use in fluid systems that provides efficient and effective sealing and alignment means used in connection with an emission containment system.